LONDON (Reuters) - Being overweight or obese is linked to a
higher risk of dying prematurely than being normal weight and
the risk rises sharply as the extra pounds pile on, scientists
said on Wednesday.

In findings contradicting the "obesity paradox," which had
suggested a possible survival advantage to being overweight,
researchers said excess body weight now causes 1 in 5 of all
premature deaths in America and 1 in 7 in Europe.

"On average, overweight people lose about one year of life
expectancy, and moderately obese people lose about three years
of life expectancy," said Emanuele Di Angelantonio from
Britain's University of Cambridge, who co-led the research.

The World Health Organization (WHO) estimates that 1.3
billion adults worldwide are overweight and a further 600
million are obese. The prevalence of adult obesity is 20 percent
in Europe and 31 percent in North America.

The negative health effects of excess body weight and its
link to chronic illnesses such as diabetes, heart disease,
stroke, respiratory disease and cancer have been well
documented. But recent studies suggesting people who are
overweight may not have lower survival rates have led to
confusion about whether obesity kills, or just causes poor
health.

This study, published in The Lancet, looked at data from
more than 10.6 million people involved in 239 large studies in
32 countries over 45 years. A combined 1.6 million deaths were
recorded across these studies, in which participants were
followed for an average of 14 years.

The researchers excluded current or former smokers, those
with chronic diseases at the beginning of the study, and any who
died in the first five years of follow-up. This left 4 million
adults to analyze.

The results showed that participants with a normal body mass
index (BMI) had the lowest premature mortality risk - of dying
before the age of 70 - during the time they were followed.

The risk of mortality increased significantly throughout the
overweight range, with every 5 units higher BMI above 25 kg/m2
linked to a 31 percent higher risk of premature death.